The Model DXT-61A 1-Button, 1-Channel Pendant Transmitter is a battery powered, portable, miniature pendant transmitter designed for use with Linear's DX Format receivers. The transmitter can be used in a limitless number of wireless remote control.The digital DX code format features over a million possible codes. Each DX transmitter is precoded at the factory to a unique code, so no field coding is required. The transmitter can send a signal for up to 10 seconds with each button activation. The DXT-61A is a one-button, one-code transmitter.